/*
 * Copyright 2002-2012 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.jdbc.core.namedparam;

import org.springframework.jdbc.core.SqlParameterValue;
import org.springframework.util.Assert;

import java.util.Collections;
import java.util.HashMap;
import java.util.Map;

/**
 * {@link SqlParameterSource} implementation that holds a given Map of parameters.
 *
 * <p>This class is intended for passing in a simple Map of parameter values
 * to the methods of the {@link NamedParameterJdbcTemplate} class.
 *
 * <p>The {@code addValue} methods on this class will make adding several
 * values easier. The methods return a reference to the {@link MapSqlParameterSource}
 * itself, so you can chain several method calls together within a single statement.
 *
 * @author Thomas Risberg
 * @author Juergen Hoeller
 * @see #addValue(String, Object)
 * @see #addValue(String, Object, int)
 * @see #registerSqlType
 * @see NamedParameterJdbcTemplate
 * @since 2.0
 */
public class MapSqlParameterSource extends AbstractSqlParameterSource {

    private final Map<String, Object> values = new HashMap<String, Object>();


    /**
     * Create an empty MapSqlParameterSource,
     * with values to be added via {@code addValue}.
     *
     * @see #addValue(String, Object)
     */
    public MapSqlParameterSource() {
    }

    /**
     * Create a new MapSqlParameterSource, with one value
     * comprised of the supplied arguments.
     *
     * @param paramName the name of the parameter
     * @param value     the value of the parameter
     * @see #addValue(String, Object)
     */
    public MapSqlParameterSource(String paramName, Object value) {
        addValue(paramName, value);
    }

    /**
     * Create a new MapSqlParameterSource based on a Map.
     *
     * @param values a Map holding existing parameter values (can be {@code null})
     */
    public MapSqlParameterSource(Map<String, ?> values) {
        addValues(values);
    }


    /**
     * Add a parameter to this parameter source.
     *
     * @param paramName the name of the parameter
     * @param value     the value of the parameter
     * @return a reference to this parameter source,
     * so it's possible to chain several calls together
     */
    public MapSqlParameterSource addValue(String paramName, Object value) {
        Assert.notNull(paramName, "Parameter name must not be null");
        this.values.put(paramName, value);
        if (value instanceof SqlParameterValue) {
            registerSqlType(paramName, ((SqlParameterValue) value).getSqlType());
        }
        return this;
    }

    /**
     * Add a parameter to this parameter source.
     *
     * @param paramName the name of the parameter
     * @param value     the value of the parameter
     * @param sqlType   the SQL type of the parameter
     * @return a reference to this parameter source,
     * so it's possible to chain several calls together
     */
    public MapSqlParameterSource addValue(String paramName, Object value, int sqlType) {
        Assert.notNull(paramName, "Parameter name must not be null");
        this.values.put(paramName, value);
        registerSqlType(paramName, sqlType);
        return this;
    }

    /**
     * Add a parameter to this parameter source.
     *
     * @param paramName the name of the parameter
     * @param value     the value of the parameter
     * @param sqlType   the SQL type of the parameter
     * @param typeName  the type name of the parameter
     * @return a reference to this parameter source,
     * so it's possible to chain several calls together
     */
    public MapSqlParameterSource addValue(String paramName, Object value, int sqlType, String typeName) {
        Assert.notNull(paramName, "Parameter name must not be null");
        this.values.put(paramName, value);
        registerSqlType(paramName, sqlType);
        registerTypeName(paramName, typeName);
        return this;
    }

    /**
     * Add a Map of parameters to this parameter source.
     *
     * @param values a Map holding existing parameter values (can be {@code null})
     * @return a reference to this parameter source,
     * so it's possible to chain several calls together
     */
    public MapSqlParameterSource addValues(Map<String, ?> values) {
        if (values != null) {
            for (Map.Entry<String, ?> entry : values.entrySet()) {
                this.values.put(entry.getKey(), entry.getValue());
                if (entry.getValue() instanceof SqlParameterValue) {
                    SqlParameterValue value = (SqlParameterValue) entry.getValue();
                    registerSqlType(entry.getKey(), value.getSqlType());
                }
            }
        }
        return this;
    }

    /**
     * Expose the current parameter values as read-only Map.
     */
    public Map<String, Object> getValues() {
        return Collections.unmodifiableMap(this.values);
    }


    public boolean hasValue(String paramName) {
        return this.values.containsKey(paramName);
    }

    public Object getValue(String paramName) {
        if (!hasValue(paramName)) {
            throw new IllegalArgumentException("No value registered for key '" + paramName + "'");
        }
        return this.values.get(paramName);
    }

}
